"There is no information on the possible causes of the crash. At this stage you have to be vigilant. Yesterday I spoke twice with my Egyptian counterpart, he said that all leads should be explored, none of them are a priority," Ayrault said in an interview with the France 2 broadcaster.
EgyptAir flight MS804 vanished off the radars in the early hours of Thursday. Countries including Greece, France and Egypt, are involved in the search operations. Despite several reports that the EgyptAir plane's wreckage has been found, the airline has said that the investigators are still searching for the remains of the missing plane.